Rotary engine.



PATENTED APR. 19, 1904.

J. S. DAVIS.

ROTARY ENGINE.

APPLIOATION rum: MAR. 14, 190.4.

2 SHEETS-SHEET 1.

N0 MODEL.

liwador' (707272 417F027?! No. 757,894. PATENTBD APR. 19, 1904.

- J. s. DAVIS.

ROTARY ENGINE.

APPLICATION FILED MAR. 14, 1904.

H0 IODEL. 2 SHEETS- 8111531 2.

WITNESSES. IN VENTOI? (707177 45. Da /WV By M A TTORNE YS mr, mums PETERS co, worc-umu, WASHINGTON. o c.

Patented. April 19, 1904..

PATENT OFFICE.

JOHN SHADERICK DAVIS, OF MONTGOMERY, ALABAMA.

ROTARY ENGINE.

srnormcmron forming pa of Letters Paten No. 757,894, dated April 19, 1904.

Application filed March 14, 1904.

T0 (bl/Z whom, it nea concern."

My invention is an improvement in the class of rotary engines--that is to say, such asa're provided with a piston adapted totravel in a circle around the shaft to which it is secured. a My lnvention is more particularly an 1m provement in that class of rotary engines in which a sliding abutment isarranged radially between the steam inlet and outlet and is operated by a cam fixed on the rotary shaft,

The detailsof construction, arrangement,

and operation of parts are as hereinafter de-' scribed, reference being had to accompanying drawings, in which I Figure l is a transverse verticalsection of the engine proper, other parts connected therewith being shownin elevation. 2 isa vertical section on the line 2 2 of Fig. 1. Fig. is a side view of the cam which operates the lever connectedwith the sliding abutment. Fig. 4 is a vertical section on the line 4 l of Fig. 1. Fig. 5 is an end view of the engine. Fig. 6 is an edgeview of a portion of the rotary piston. Fig. 7 isa side view illustrating a modification, and Fig. 8 is a vertical section on the line 8 8 of Fig. 7. t

The parts composing the engine properare arranged in a suitable frame A. The piston B consists of a metal plate of circular form having a peripheral projection 0, against which the steam acts. As shown in Fig. 1, two thick circular plates D are arranged on opposite sides of the piston B andsecured together and to it by screw-bolts. These disks may be constructed of metal, and they serve not only to stiffen the piston-plate B, but to add weight thereto, so as to dispense with the necessity of using a fly or balance wheel. The piston and disks are keyed upon the shaft E, which is arranged horizontally and which will in practice be suitably connected with machinery to be driven. The edge of the piston B projects beyond the disk D and through a slot Serial No. 198,178. (No model.)

formed in the inner side of an annular steamchamber formed by grooving two plates F F, which are in this case rectangular and securelybolted in the frame A in vertical position. (See especially Figs. 2 and 5.) It will be understood that each of the said plates F is grooved on its inner side, and when the grooves are brought together in coincidence, as in Fig. 1, they form a circular steam-passage G, "(See also Fig. 2.) The peripheral projection C of the'pis'ton B is adapted to fit somewhat closely in this annular steam-passage G. Steam is admitted through a pipe H and exhausts through a corresponding pipe I, as illustrated in Figs. 2 and 4:. Between these pipes is arranged the sliding abutment J which is a metal plate having parallel sides and adapted to slide Vertically in a slot or passage provided in the plates F. The said abutment is connected by a link K with a rightangular lever L, one end of which is pivoted to the upper portion of the frame A and whose pendent arm rests upon a cam M, keyed upon the shaft E. A spiral spring N is attached to the lever L at a point exterior to the abutment and connected with the plates F. This spring supplements gravity in holding the lever L duly engaged with the cam M.

The operation of my improved engine will now be understood to be as follows: Steam being admitted by the pipe H when the abutment J is in its lowest position, as shown in Figs. 1 and 2, the steam acts between said abutment and the peripheral projection or block ofthe piston, and thereby rotates the latter, the piston-block being carried around in the annular passage Gr. Just before the block reaches the abutment J the cam acting upon the lever L raises the same, so that the abutment is raised high enough to allow the block C to pass beneath it. When the lever falls to its former position and the abutment J is moved down to its former position, (indicated in Figs. 1 and 2,) then the steam again acts upon the piston as before. As will be understood, the steam escapes from the annular passage G just as the piston-block C is passing the abutment J.

In practice the lower end of the vertical understood. Aspiral spring N is attached to member of the lever L may be provided with a roller to relieve friction between it and the cam M.

The piston-disk B may be constructed of steel or any other metal having suitable qualities. The block C, against which the steam acts, may be constructed as a hollow metal cylinder, provided with a circular enlarged head or flange, and it may be attached to the piston proper by'a loop or band I), (see Fig. 2,) the reduced diameter of the body of the block C allowing space for such band in the annular steam-passage G. The band may be formed integral with the disk B as a radial projection thereof, it being subsequently bent inward and its free end brazed or otherwise secured, so as to hold the block 0 securely. In Fig. l friction or wear plates f are shown arranged on the inner side of the steam-passage Gr. It is to be understood that the said passage may be lined in this manner throughout or inay be bushed entirely.

The plates F are preferably formed of cast metal and may be thus producedvery cheaply. In fact, all the working parts are constructed of metal and may be'produced very inexpensively. The engine is thus distinguished by simplicity, strength, durability, and economy of construction.

In Figs. 7 and 8 I illustrate a modification in which the lever L is shown extended and its outer endworking in a guide-slot in a portion of the frame and also resting when in its lowest position on an abutment formed by the bottom of the slot. The cam M is shown provided with an 'acute-angled'tangential projection and the lever L is provided with a pendent arm Z, whose lower end is acute angled or beveled to adapt it to coact with the cam projection,as will be readily the frame at its lower end and to the lever L at its upper end. The operation of the parts is substantially the same as in the case first described. i

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The improved rotary engine comprising the horizontal shaft, a metal disk secured thereto and having a peripheral projection whereby it is adapted to serve as a piston,

opposite plates having coincident annular grooves forming a steampassage, an abutment adapted to slide radially in said plates, steam inlet and outlet pipes connected with the'plates and communicating with the steampassage, an angular lever pivoted at a fixed point, and a link connecting it with the sliding abutment, a cam fixed on the aforesaid shaft and working in contact with the pendent end of the lever, and a spring coacting with said lever for holding it in working contact with the cam, substantially as described.

2. In a rotary engine of the class specified, the combination, with parts forming an annular steam-passage, inlet and outlet steampipes, a sliding abutment, and means for operating the same, of a piston formed of a metal plate having a peripheral projection adapted to work in the steam-passage, and heavy plates secured on opposite sides of said disk and having less diameter than the disk so that they are surrounded by the parts forming the annular steam-passage, substantially as described.

3. In a rotary engine of the class specified, the combination, with the shaft, the cam fixed thereto, a rotary piston, and parts forming an annular steam-passage, of a right-angular lever pivoted at a fixed point above the engine proper, and having a pendent free arm which works-in contact with the cam, and a sliding abutment connected with said lever at a point between its fulcrum and pendent arm, substantially as described. I r

4. In a rotary engine of the class specified, the combination with the shaft, a cam fixed thereto, a rotary piston, and parts forming an annular steam-passage, of a lever pivoted at a fixed point above the engine proper and having a pendent arm which works in contact with the cam, and asliding abutment connected with the lever at a point between its fulcrum and arm substantially as described.

5. In a rotary'engine of the class specified, the piston composed of a metal disk having a peripheral loop and a block secured in said loop and serving as a steam-head, substantially as described.

JOHN SHADERICK DAVIS. Witnesses:

1. C. MASSIE, O. V. WILSON. 

